烟草(Nicotiana tabacum)原生质体再生成植株及影响植株分化的某些因素

从烟草(品种革新一号)单倍体花粉植株的叶和茎产生的愈伤组织,结合悬浮培养,获得的细胞分离出原生质体。在液体培养基中静置培养,12小时后原生质体开始变为卵圆形,细胞壁明显可见,24小时后完成第一次细胞分裂。以后继续分裂形成浅黄色的愈伤组织,在培养四星期后可达1毫米大小,再放到转床上进行旋转培养18天左右,愈伤组织可达3—4毫米大小。当转移到分化培养基后,分别分化出苗及根,长成完整的植株。 原生质体再生细胞的分裂与分化,不仅受不同器官来源的愈伤组织及其年龄的影响;还受分化培养基的基本成份及所用细胞分裂素的类型等的影响。     

叶轮机械设计自变数在内外环壁面上的限制条件及轴流式叶轮机械S1流面的翘曲

本文利用中心流面法的概念,指出叶轮机械的设计白变数在内、外环壁面上应有附加的限制条件,并导得其具体简明方程。同时,还定性地分析了S₁流面的翘曲情况。     

Spin-lattice relaxation of CH4 gas in a deuterated clathrate lattice

The proton T₁ temperature dependence of CH₄ gas in a deuterated clathrate lattice deviates from the semiclassifical predictions. The discrepancy is partially accounted for by including the effects of symmetry and the quantization of rotational states.     

超导临界温度理论(Ⅰ)

本文求出了Eliashberg方程在T=T_c时的解,得到了下面的临界温度级数表示式: 其中α₀(μ^*),α₁(μ^*)等系数是μ^*的函数.此式表明,T_c不仅依赖于λ,〈ω²〉和μ^*,而且依赖于有效声子谱α²F(ω)的各级矩〈ω²n〉.这是区别于前人的T_c公式最重要的一点。这说明像McMillan以及Allen和Dynes的T_c公式不仅是近似的,而主要是他们没有能正确地概括出α²F(ω)对T_c的影响.     

Postselective two-photon interference from a continuous nonclassical stream of photons emitted by a quantum dot

We report an electrically driven semiconductor single-photon source capable of emitting photons with a coherence time of up to 400 ps under fixed bias. It is shown that increasing the injection current causes the coherence time to reduce, and this effect is well explained by the fast modulation of a fluctuating environment. Hong-Ou-Mandel-type two-photon interference using a Mach-Zehnder interferometer is demonstrated using this source to test the indistinguishability of individual photons by postselecting events where two photons collide at a beam splitter. Finally, we consider how improvements in our detection system can be used to achieve a higher interference visibility.     

三维光存储中折射率失配引起的球差补偿

为实现三维光存储中折射率失配引起的球差补偿,建立了光学存储系统模型,获得了折射率失配引起的波前偏差函数与存储深度的表达式.采用泽尔尼克循环多项式对波前偏差函数进行补偿展开.在双光子荧光和单光子共焦荧光读出方式下,均可获得读出荧光强度与存储深度的关系:在折射率失配引起的球差未得到补偿矫正的情况下,存储深度在200 μm左右读出荧光强度基本上下降为零;当折射率失配引起的初级球差被补偿矫正后,读出荧光强度随存储深度的下降得到较好改善;当折射率失配引起的二级球差被补偿矫正后,存储深度在1 mm内存储点强度随深度基本上没有明显地变化.并且对像差补偿方法进行了具体地分析.     

高温高密度氦的压缩特性及其结构的分子动力学模拟

用分子动力学方法和不同参数的指数 6势函数计算了T =30 4K的高密度氦的等温压缩线和能量分布 .给出了能精确描述高密度氦原子间相互作用的指数 6势函数优化参数 .并用优化的势函数计算了高密度氦T =30 0K和T =2 98K的等温压缩线 ,计算结果和实验值非常吻合 .进一步用优化的势函数模拟了高温高密度氦的状态方程及其结构 ,发现当把 ρ限定为 1 .6 0g /cm³ 时 ,其径向分布函数的第 2个峰将在 2 0 0 0～ 30 40K区间消失 ,表明此时发生了固 液相变过程 .     

使用色散可调啁啾光纤光栅在常规单模光纤中实现超过100km,10Gb/s的转输 *

报道了用简单的应力方法使均匀光栅成为线性啁啾光纤光栅的技术 ,并推导出了相应理论 ,发现最大色散补偿带宽与色散的乘积近似为常数 .在常规单模光纤G652,10Gb/s系统中实现超过100km的色散补偿 .     

Resonance-enhanced multiphoton ionisation photoelectron spectroscopy of the ClO radical: the C 2 sigma- state

A (2 + 1) one-colour resonance-enhanced multiphoton ionisation study is carried out on the C 2 sigma- state of the ClO radical in the one-photon energy range 29,500-31,250 cm-1. The ClO radical is produced by one-photon photolysis of ClO2 employing 359.2 nm photons derived from a separate laser. In this way a significant concentration of vibrationally excited ClO in its spin-orbit split X 2 pi omega (omega = 3/2 or 1/2) electronic ground state is produced. In addition to mass-resolved excitation spectra, kinetic-energy resolved photoelectron spectra for the X 3 sigma-(v+)<--C 2 sigma-(v' = 3-5) transitions are measured. These transitions are not completely Frank-Condon diagonal, and indicate a decrease in bond length on removal of the Rydberg electron from the C 2 sigma- state. In addition to an unambiguous assignment of the C 2 sigma- state, valuable information is obtained on the degree of vibrational excitation with which the nascent ClO radical is formed in the photolysis of ClO2. Analysis of the photoelectron spectra is supported by Franck-Condon calculations based on potential energy curves either from experimental spectroscopic parameters, or obtained by theoretical ab initio methods.